{%  load mytag %}
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title> template</title>
</head>
<body>
{{content | default:'No content'}}
{# 关闭转义， 可以使用  #}
{% autoescape off %}
  {{ content }}
{%  endautoescape %}
<p> {{ num | add:'10' }}</p>
<p> {{ 5 | sub1}}</p>
</body>
</html>
